Thermochemistry and Thermodynamics Test 2

Total Questions:50 Total Time: 75 Min



Questions 1 of 50

Question:Which of the following units represents the largest amount of energy

Answers Choices:

Electron volt




Questions 2 of 50

Question:Energy equivalent to one erg, one joule and one calorie is in the order

Answers Choices:

\(1\,erg\, > \,1\,joule\, > \,1\,calorie\)

\(1\,erg\, > \,1\,calorie\, > \,1\,joule\)

\(1\,calorie\, > \,1\,joule\, > \,1\,erg\)

\(1\,joule\, > \,1\,calorie\, > \,1\,erg\)

Questions 3 of 50

Question:In thermodynamics which one of the following is not an intensive property

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Questions 4 of 50

Question:If in a container neither mass and nor heat exchange occurs then it constitutes a

Answers Choices:

Closed system

Open system

Isolated system

Imaginary system

Questions 5 of 50

Question:"The resultant heat change in a reaction is the same whether it takes place in one or several stages." This statement is called

Answers Choices:

Lavoisier and Laplace law

Hess's law

Joule's law

Le'chatelier's principle

Questions 6 of 50

Question:Hess's law of constant heat summation in based on

Answers Choices:

\(E = m{c^2}\)

Conservation of mass

First law of thermodynamics

None of the above

Questions 7 of 50

Question:The relation between change in internal energy \((\Delta E)\), change in enthalpy \((\Delta H)\) and work done (W) is represented as

Answers Choices:

\(\Delta H = \Delta E + W\)

\(W = \Delta E - \Delta H\)

\(\Delta E = W - \Delta H\)

\(\Delta E = \Delta H + W\)

Questions 8 of 50

Question:The enthalpy of neutralization of which of the following acids and bases is nearly \( - 13.6\,Kcal\)

Answers Choices:

HCN and NaOH

HCl and KOH

HCl and NaOH

HCl and \(N{H_4}OH\)

2 and 3 are correct

Questions 9 of 50

Question:The work done by a system is 8 joule, when 40 joule heat is supplied to it. What is the increase in internal energy of system

Answers Choices:

25 J

30 J

32 J

28 J

Questions 10 of 50

Question:A system absorb 600J of heat and work equivalent to 300J on its surroundings. The change in internal energy is

Answers Choices:

300 J

400 J

500 J

600 J

Questions 11 of 50

Question:Work done during isothermal expansion of one mole of an ideal gas from 10 atom. to 1 atm at 300K is

Answers Choices:

4938.8 J

4138.8 J

5744.1 J

6257.2 J

Questions 12 of 50

Question:For a reversible spontaneous change \(\Delta S\) is

Answers Choices:

\(\frac{{\Delta E}}{T}\)

\(\frac{{P\,\Delta V}}{T}\)


RT log K

Questions 13 of 50

Question:When disorder of a system increases, the change is said to be

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Questions 14 of 50

Question:The spontaneous flow of heat is always

Answers Choices:

From low to high pressure

From high to high pressure

Unidirectional from lower temperature to higher temperature

Unidirectional from the higher to lower temperature

Questions 15 of 50

Question:The occurrence of a reaction is impossible if

Answers Choices:

\(\Delta H\) is +ve ; \(\Delta S\) is also + ve but \(\Delta H < T\Delta S\)

\(\Delta H\) is – ve ; \(\Delta S\) is also – ve but \(\Delta H\, > \,T\Delta S\)

\(\Delta H\) is – ve ; \(\Delta S\) is + ve

\(\Delta H\) is + ve ; \(\Delta S\) is – ve

Questions 16 of 50

Question:If the enthalpy of vaporization for water is 186.5 kJ \(mo{l^{ - 1}}\), the entropy of its vaporization will be

Answers Choices:

\(0.5\,J{K^{ - 1}}mo{l^{ - 1}}\)

\(1.0\,J{K^{ - 1}}mo{l^{ - 1}}\)

\(1.5\,J{K^{ - 1}}mo{l^{ - 1}}\)

\(2.0\,J{K^{ - 1}}mo{l^{ - 1}}\)

Questions 17 of 50

Question:Which of the following statement is true. The entropy of the universe

Answers Choices:

Increases and tends towards maximum value

Decreases and tends to be zero

Remains constant

Decreases and increases with a periodic rate

Questions 18 of 50

Question:One mole of an ideal gas at \(300K\) is expanded isothermally from an initial volume of 1 litre to 10 litres. The change in energy for this process is \((R = 2\,cal\,mo{l^{ - 1}}{K^{ - 1}})\)

Answers Choices:

163.7 cal

850.2 cal

1381.1 cal


Questions 19 of 50

Question:If \(900\,J/g\) of heat is exchanged at boiling point of water, then what is increase in entropy

Answers Choices:

43.4 J/mole

87.2 J/mole

900 J/mole


Questions 20 of 50

Question:A container has hydrogen and oxygen mixture in ratio of 4 : 1 by weight, then

Answers Choices:

Internal energy of the mixture decreases

Internal energy of the mixture increases

Entropy of the mixture increases

Entropy of the mixture decreases

Questions 21 of 50

Question:Equal volumes of monoatomic and diatomic gases at same initial temperature and pressure are mixed. The ratio of specific heats of the mixture \(({C_p}/{C_v})\) will be

Answers Choices:





Questions 22 of 50

Question:The law formulated by Dr. Nernst is

Answers Choices:

First law of thermodynamics

Second law of thermodynamics

Third law of thermodynamics

Both 1 and 2

Questions 23 of 50

Question:Entropy is maximum in case of

Answers Choices:


Water at \({0^o}C\)

Water at \({4^o}C\)


Questions 24 of 50

Question:Considering entropy (S) as a thermodynamic parameter, the criterion for the spontaneity of any process is

Answers Choices:

\(\Delta {S_{system}} > 0\) only

\(\Delta {S_{surroundings}} > 0\) only

\(\Delta {S_{system}} + \Delta {S_{surroundings}} > 0\)

\(\Delta {S_{system}} - \Delta {S_{surroundings}} > 0\)

Questions 25 of 50

Question:An exothermic reaction is one which

Answers Choices:

Takes place only on heating

Is accompanied by a flame

Is accompanied by a absorption of heat

Is accompanied by evolution of heat

Questions 26 of 50

Question:An endothermic reaction is one in which

Answers Choices:

Heat is converted into electricity

Heat is absorbed

Heat is evolved

Heat is converted into mechanical work

Questions 27 of 50

Question:The enthalpy of combustion at 25\(^\circ \)C of \({H_2}\), cyclohexane (C\(_{\rm{6}}\)H\(_{{\rm{12}}}\)) and cyclohexene (C\(_{\rm{6}}\)H\(_{{\rm{1}}0}\)) are -241, -3920 and -800 KJ / mole respectively. The heat of hydrogenation of cyclohexene is

Answers Choices:

121 KJ / mole

+ 121 KJ / mole

242 KJ / mole

+ 242 KJ / mole

Questions 28 of 50

Question:Heat of neutralisation of \(N{H_4}OH\) and \(HCl\) is

Answers Choices:


\( > \,13.7\,kcal\)

\( < \,13.7\,kcal\)

None of the above

Questions 29 of 50

Question:The heat of combustion of carbon is –94 kcal at 1 atm pressure. The intrinsic energy of \(C{O_2}\) is

Answers Choices:

\( + 94\,kcal\)

\( - \,94\,kcal\)

\( + 47\,kcal\)

\( - 47\,kcal\)

Questions 30 of 50

Question:The heat of neutralisation of a strong acid and a strong alkali is \(57.0\,kJ\,mo{l^{ - 1}}\). The heat released when \(0.5\,mole\) of \(HN{O_3}\) solution is mixed with \(0.2\,mole\) of \(KOH\) is

Answers Choices:





Questions 31 of 50

Question:One of the phenomena which cannot be described as combustion is

Answers Choices:

Oxidation of coal in air

Burning of magnesium in nitrogen

Reaction of antimony in chlorine

Lighting of an electric lamp

Questions 32 of 50

Question:Which of the following statements is correct about heat of combustion

Answers Choices:

It may be exothermic in some cases and endothermic in other cases

It is applicable to gaseous substances only

It is always an exothermic reaction

Its value does not change with temperature

Questions 33 of 50

Question:Based on the following thermochemical equations \({H_2}O(g) + C(s) \to CO(g) + {H_2}(g);\,\Delta H = 131\,kJ\), \(CO(g) + \frac{1}{2}{O_2}(g) \to C{O_2}(g);\Delta H = - 282\,kJ\), \({H_2}(g) + \frac{1}{2}{O_2}(g) \to {H_2}O(g);\,\Delta H = - 242\,kJ\) , \(C(s) + {O_2}(g) \to C{O_2}(g);\,\Delta H = X\,kJ\) . The value of \(X\) is

Answers Choices:

\( - 393\,kJ\)

\( - \,655\,kJ\)

\( + \,393\,kJ\)

\( + 655\,kJ\)

Questions 34 of 50

Question:Heat of transition is the heat evolved or absorbed when a substance is converted from

Answers Choices:

Solid to liquid

Solid to vapour

Liquid to vapour

One allotropic form to another allotropic form

Questions 35 of 50

Question:In an endothermic reaction, the value of \(\Delta H\) is

Answers Choices:





Questions 36 of 50

Question:\(2.2016\,gm\) of acetaldehyde produced \(13.95\,kcal\) of heat on combustion in \({O_2}\). Calculate the heat of combustion of \(C{H_3}CHO\)

Answers Choices:

279 kcal

972 kcal

27.9 kcal

2.79 kcal

Questions 37 of 50

Question:The neutralisation of a strong acid by a strong base liberates an amount of energy per mole of \({H^ + }\) that

Answers Choices:

Depends upon which acid and base are involved

Depends upon the temperature at which the reaction takes place

Depends upon which catalyst is used

Is always the same

Questions 38 of 50

Question:When \(0.5g\) of sulphur is burnt to \(S{O_2},\,4.6\,kJ\) of heat is liberated. What is the enthalpy of formation of sulphur dioxide

Answers Choices:

+ 147.2 kJ

147.2 kJ

294.4 kJ

+ 294.4 kJ

Questions 39 of 50

Question:\({H_2}(g) + C{l_2}(g)\,\, \to \,\,2HCl(g)\,.\,\Delta H = - 44kcal\), \(2Na(s) + 2HCl(g)\,\, \to \,\,2NaCl(s) + {H_2}(g),\)\(\Delta H = - 152\,kcal\), For the reaction \(Na(s) + \frac{1}{2}C{l_2}(g)\,\, \to \,\,NaCl(s),\,\Delta H = \)

Answers Choices:

-108 kcal

-196 kcal

-98 kcal

-54 kcal

Questions 40 of 50

Question:The \(\Delta H_f^o\) for \(C{O_2}(g),\,CO(g)\) and \({H_2}O(g)\) are -393.5, -110.5 and -241.8kJmol\(^{ - 1}\) respectively. The standard enthalpy change (in kJ) for the reaction \(C{O_2}(g) + {H_2}(g) \to \) \(CO(g) + {H_2}O(g)\) is

Answers Choices:





Questions 41 of 50

Question:Heat of neutralization of strong acid and weak base is

Answers Choices:

\(57.1\,kJ\,mo{l^{ - 1}}\)

\(13.7\,kJ\,mo{l^{ - 1}}\)

Less than \(13.7\,kcal\,mo{l^{ - 1}}\)

More than \(13.7\,kcal\,mo{l^{ - 1}}\)

Questions 42 of 50

Question:A system is changed from state A to state B by one path and from B to A another path. If \({E_1}\) and \({E_2}\) are the corresponding changes in internal energy, then

Answers Choices:

\({E_1} + {E_2} = - ve\)

\({E_1} + {E_2} = + ve\)

\({E_1} + {E_2} = 0\)

None of these

Questions 43 of 50

Question:One gram sample of \(N{H_4}N{O_3}\) is decomposed in a bomb calorimeter. The temperature of the calorimeter increases by 6.12 K the heat capacity of the system is 1.23 kJ/g/deg. What is the molar heat of decomposition for \(N{H_4}N{O_3}\)

Answers Choices:

7.53 kJ/mol

398.1 kJ/mol

16.1 kJ/mol

602 kJ/mol

Questions 44 of 50

Question:For which one of the following equations is \(\Delta H_{{\rm{react}}}^o\) equal to \(\Delta H_f^o\) for the product

Answers Choices:

\(2CO(g) + {O_2}(g)\, \to \,2C{O_2}(g)\)

\({N_2}(g) + {O_3}(g)\, \to \,{N_2}{O_3}(g)\)

\(C{H_4}(g) + 2C{l_2}(g)\, \to \,C{H_2}C{l_2}(l) + 2HCl(g)\)

\(Xe(g) + 2{F_2}(g)\, \to \,Xe{F_4}(g)\)

Questions 45 of 50

Question:If the bond dissociation energies of \(XY,\,{X_2}\)and \({Y_2}\) (all diatomic molecules) are in the ratio of 1 : 1 : 0.5 and \({\Delta _f}H\) for the formation of \(XY\) is \( - 200\,kJ\,mol{e^{ - 1}}\). The bond dissociation energy of \({X_2}\) will be

Answers Choices:

\(100\,kJ\,mo{l^{ - 1}}\)

\(800\,kJ\,mo{l^{ - 1}}\)

\(300\,kJ\,mo{l^{ - 1}}\)

\(400\,kJ\,mo{l^{ - 1}}\)

Questions 46 of 50

Question:Energy required to dissociate 4 gm of gaseous hydrogen into free gaseous atoms is 208 kcal at \({25^o}C\). The bond energy of \(H - H\) bond will be

Answers Choices:

104 kcal

10.4 kcal

1040 kcal

104 cal

Questions 47 of 50

Question:For precipitation reaction of \(A{g^ + }\) ions with \(NaCl\), which of the following statements is correct

Answers Choices:

\(\Delta H\) for the reaction is zero

\(\Delta G\) for the reaction is zero

\(\Delta G\) for the reaction is negative

\([\Delta G] = [\Delta H]\)

Questions 48 of 50

Question:At constant pressure and temperature, the direction to the result of any chemical reaction is where, there is less amount of

Answers Choices:



Gibb's free energy

None of the above

Questions 49 of 50

Question:The equilibrium concentration of the species in the reaction \(A + B \equiv C + D\) are 3, 5, 10 and 15 \(mole\,{L^{ - 1}}\) respectively at \(300\,K\) the \(\Delta G\) for the reaction is

Answers Choices:





Questions 50 of 50

Question:Gibb's free enrgy \((G)\) is defined as

Answers Choices:

\(\Delta G = \Delta H - T\Delta S\)

\(\Delta G = \Delta H + \frac{T}{{\Delta S}}\)

\(\Delta H = \Delta G - T\Delta S\)

\(\Delta G = \Delta H + T.{C_p}\)